diff mbox series

[v5,05/19] mtd: spi-nor: add support for DTR protocol

Message ID 20200519142642.24131-6-p.yadav@ti.com (mailing list archive)
State Superseded
Headers show
Series mtd: spi-nor: add xSPI Octal DTR support | expand

Commit Message

Pratyush Yadav May 19, 2020, 2:26 p.m. UTC
Double Transfer Rate (DTR) is SPI protocol in which data is transferred
on each clock edge as opposed to on each clock cycle. Make
framework-level changes to allow supporting flashes in DTR mode.

Right now, mixed DTR modes are not supported. So, for example a mode
like 4S-4D-4D will not work. All phases need to be either DTR or STR.

Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
---
 drivers/mtd/spi-nor/core.c  | 305 ++++++++++++++++++++++++++++--------
 drivers/mtd/spi-nor/core.h  |   6 +
 drivers/mtd/spi-nor/sfdp.c  |   9 +-
 include/linux/mtd/spi-nor.h |  51 ++++--
 4 files changed, 295 insertions(+), 76 deletions(-)

Comments

Mason Yang May 21, 2020, 9:24 a.m. UTC | #1
Hi Pratyush,


> @@ -311,6 +313,7 @@ struct flash_info {
>                  * BP3 is bit 6 of status register.
>                  * Must be used with SPI_NOR_4BIT_BP.
>                  */
> +#define SPI_NOR_OCTAL_DTR_READ   BIT(19) /* Flash supports octal DTR 
Read. */

#define SPI_NOR_OCTAL_DTR_RDWR  BIT(19) /* Support Octal DTR Read & Write 
*/

more precisely and clearly ?

thanks,
Mason

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=====================================================================



============================================================================

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=====================================================================
Pratyush Yadav May 21, 2020, 12:52 p.m. UTC | #2
Hi,

On 21/05/20 05:24PM, masonccyang@mxic.com.tw wrote:
> 
> Hi Pratyush,
> 
> 
> > @@ -311,6 +313,7 @@ struct flash_info {
> >                  * BP3 is bit 6 of status register.
> >                  * Must be used with SPI_NOR_4BIT_BP.
> >                  */
> > +#define SPI_NOR_OCTAL_DTR_READ   BIT(19) /* Flash supports octal DTR 
> Read. */
> 
> #define SPI_NOR_OCTAL_DTR_RDWR  BIT(19) /* Support Octal DTR Read & Write 
> */

This flag only enables SNOR_HWCAPS_READ_8_8_8_DTR. It does not affect 
SNOR_HWCAPS_PP_8_8_8_DTR. So it shouldn't be called RDWR.
 
> more precisely and clearly ?
> 
> thanks,
> Mason
>
Mason Yang May 22, 2020, 6:30 a.m. UTC | #3
Hi Pratyush,


> +/**
> + * spi_nor_spimem_setup_op() - Set up common properties of a spi-mem 
op.
> + * @nor:      pointer to a 'struct spi_nor'
> + * @op:         pointer to the 'struct spi_mem_op' whose properties
> + *         need to be initialized.
> + * @proto:      the protocol from which the properties need to be set.
> + */
> +void spi_nor_spimem_setup_op(const struct spi_nor *nor,
> +              struct spi_mem_op *op,
> +              const enum spi_nor_protocol proto)
> +{
> +   u8 ext;
> +
> +   op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(proto);
> +
> +   if (op->addr.nbytes)
> +      op->addr.buswidth = spi_nor_get_protocol_addr_nbits(proto);
> +
> +   if (op->dummy.nbytes)
> +      op->dummy.buswidth = spi_nor_get_protocol_addr_nbits(proto);
> +
> +   if (op->data.nbytes)
> +      op->data.buswidth = spi_nor_get_protocol_data_nbits(proto);
> +
> +   if (spi_nor_protocol_is_dtr(proto)) {

As mentioned before that I am also patching mx25* which supports 8S-8S-8S 
and 
8D-8D-8D mode.

please patch to spi_nor_protocol_is_8_8_8(proto) for 8S-8S-8S mode 
support.

> +      /*
> +       * spi-mem supports mixed DTR modes, but right now we can only
> +       * have all phases either DTR or STR. IOW, spi-mem can have
> +       * something like 4S-4D-4D, but spi-nor can't. So, set all 4
> +       * phases to either DTR or STR.
> +       */

        if (spi_nor_protocol_is_8D_8D_8D(proto) {

> +      op->cmd.dtr = op->addr.dtr = op->dummy.dtr
> +                = op->data.dtr = true;
> +
> +      /* 2 bytes per clock cycle in DTR mode. */
> +      op->dummy.nbytes *= 2;

        }

> +
> +      ext = spi_nor_get_cmd_ext(nor, op);
> +      op->cmd.opcode = (op->cmd.opcode << 8) | ext;
> +      op->cmd.nbytes = 2;
> +   }
> +}
> +

thanks & best regards,
Mason


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and/or personal data, which is protected by applicable laws. Please be 
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(and/or its attachments) or any part thereof is prohibited. If you receive 
this e-mail in error, please notify us immediately and delete this mail as 
well as its attachment(s) from your system. In addition, please be 
informed that collection, processing, and/or use of personal data is 
prohibited unless expressly permitted by personal data protection laws. 
Thank you for your attention and cooperation.

Macronix International Co., Ltd.

=====================================================================



============================================================================

CONFIDENTIALITY NOTE:

This e-mail and any attachments may contain confidential information and/or personal data, which is protected by applicable laws. Please be reminded that duplication, disclosure, distribution, or use of this e-mail (and/or its attachments) or any part thereof is prohibited. If you receive this e-mail in error, please notify us immediately and delete this mail as well as its attachment(s) from your system. In addition, please be informed that collection, processing, and/or use of personal data is prohibited unless expressly permitted by personal data protection laws. Thank you for your attention and cooperation.

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=====================================================================
Pratyush Yadav May 22, 2020, 8:37 a.m. UTC | #4
On 22/05/20 02:30PM, masonccyang@mxic.com.tw wrote:
> 
> Hi Pratyush,
> 
> 
> > +/**
> > + * spi_nor_spimem_setup_op() - Set up common properties of a spi-mem 
> op.
> > + * @nor:      pointer to a 'struct spi_nor'
> > + * @op:         pointer to the 'struct spi_mem_op' whose properties
> > + *         need to be initialized.
> > + * @proto:      the protocol from which the properties need to be set.
> > + */
> > +void spi_nor_spimem_setup_op(const struct spi_nor *nor,
> > +              struct spi_mem_op *op,
> > +              const enum spi_nor_protocol proto)
> > +{
> > +   u8 ext;
> > +
> > +   op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(proto);
> > +
> > +   if (op->addr.nbytes)
> > +      op->addr.buswidth = spi_nor_get_protocol_addr_nbits(proto);
> > +
> > +   if (op->dummy.nbytes)
> > +      op->dummy.buswidth = spi_nor_get_protocol_addr_nbits(proto);
> > +
> > +   if (op->data.nbytes)
> > +      op->data.buswidth = spi_nor_get_protocol_data_nbits(proto);
> > +
> > +   if (spi_nor_protocol_is_dtr(proto)) {
> 
> As mentioned before that I am also patching mx25* which supports 8S-8S-8S 
> and 
> 8D-8D-8D mode.
> 
> please patch to spi_nor_protocol_is_8_8_8(proto) for 8S-8S-8S mode 
> support.

Like I said before, we should try to avoid creeping up the scope of this 
series. This series aims to add 8D support. Once this lands, I don't see 
why you can't 8S support on top. Unless we make a fundamental change 
that makes it impossible to add 8S support, it should stay as-is.

All that said, I fail to see why 8S would have any problems with this 
function. We just fill in the buswidths from the protocol, and adjust 
the op if it is DTR. So in case of 8S mode, this function as it is will 
fill in the buswidths to 8 for all phases. And it won't hit the if block 
here so this code is of no concern to 8S mode.
 
> > +      /*
> > +       * spi-mem supports mixed DTR modes, but right now we can only
> > +       * have all phases either DTR or STR. IOW, spi-mem can have
> > +       * something like 4S-4D-4D, but spi-nor can't. So, set all 4
> > +       * phases to either DTR or STR.
> > +       */
> 
>         if (spi_nor_protocol_is_8D_8D_8D(proto) {

No. The adjustments below apply to _all_ DTR ops, not just 8D-8D-8D 
ones. So in case someone wants to use 4D-4D-4D mode, they won't have to 
touch this code at all.
 
> > +      op->cmd.dtr = op->addr.dtr = op->dummy.dtr
> > +                = op->data.dtr = true;
> > +
> > +      /* 2 bytes per clock cycle in DTR mode. */
> > +      op->dummy.nbytes *= 2;
> 
>         }
> 
> > +
> > +      ext = spi_nor_get_cmd_ext(nor, op);
> > +      op->cmd.opcode = (op->cmd.opcode << 8) | ext;
> > +      op->cmd.nbytes = 2;
> > +   }
> > +}
> > +
diff mbox series

Patch

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index 1ab4386a099a..388e695e763f 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -40,6 +40,76 @@ 
 
 #define SPI_NOR_MAX_ADDR_WIDTH	4
 
+/**
+ * spi_nor_get_cmd_ext() - Get the command opcode extension based on the
+ *			   extension type.
+ * @nor:		pointer to a 'struct spi_nor'
+ * @op:			pointer to the 'struct spi_mem_op' whose properties
+ *			need to be initialized.
+ *
+ * Right now, only "repeat" and "invert" are supported.
+ *
+ * Return: The opcode extension.
+ */
+static u8 spi_nor_get_cmd_ext(const struct spi_nor *nor,
+			      const struct spi_mem_op *op)
+{
+	switch (nor->cmd_ext_type) {
+	case SPI_NOR_EXT_INVERT:
+		return ~op->cmd.opcode;
+
+	case SPI_NOR_EXT_REPEAT:
+		return op->cmd.opcode;
+
+	default:
+		dev_err(nor->dev, "Unknown command extension type\n");
+		return 0;
+	}
+}
+
+/**
+ * spi_nor_spimem_setup_op() - Set up common properties of a spi-mem op.
+ * @nor:		pointer to a 'struct spi_nor'
+ * @op:			pointer to the 'struct spi_mem_op' whose properties
+ *			need to be initialized.
+ * @proto:		the protocol from which the properties need to be set.
+ */
+void spi_nor_spimem_setup_op(const struct spi_nor *nor,
+			     struct spi_mem_op *op,
+			     const enum spi_nor_protocol proto)
+{
+	u8 ext;
+
+	op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(proto);
+
+	if (op->addr.nbytes)
+		op->addr.buswidth = spi_nor_get_protocol_addr_nbits(proto);
+
+	if (op->dummy.nbytes)
+		op->dummy.buswidth = spi_nor_get_protocol_addr_nbits(proto);
+
+	if (op->data.nbytes)
+		op->data.buswidth = spi_nor_get_protocol_data_nbits(proto);
+
+	if (spi_nor_protocol_is_dtr(proto)) {
+		/*
+		 * spi-mem supports mixed DTR modes, but right now we can only
+		 * have all phases either DTR or STR. IOW, spi-mem can have
+		 * something like 4S-4D-4D, but spi-nor can't. So, set all 4
+		 * phases to either DTR or STR.
+		 */
+		op->cmd.dtr = op->addr.dtr = op->dummy.dtr
+			       = op->data.dtr = true;
+
+		/* 2 bytes per clock cycle in DTR mode. */
+		op->dummy.nbytes *= 2;
+
+		ext = spi_nor_get_cmd_ext(nor, op);
+		op->cmd.opcode = (op->cmd.opcode << 8) | ext;
+		op->cmd.nbytes = 2;
+	}
+}
+
 /**
  * spi_nor_spimem_bounce() - check if a bounce buffer is needed for the data
  *                           transfer
@@ -104,14 +174,12 @@  static ssize_t spi_nor_spimem_read_data(struct spi_nor *nor, loff_t from,
 	ssize_t nbytes;
 	int error;
 
-	/* get transfer protocols. */
-	op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->read_proto);
-	op.addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->read_proto);
-	op.dummy.buswidth = op.addr.buswidth;
-	op.data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto);
+	spi_nor_spimem_setup_op(nor, &op, nor->read_proto);
 
 	/* convert the dummy cycles to the number of bytes */
 	op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
+	if (spi_nor_protocol_is_dtr(nor->read_proto))
+		op.dummy.nbytes *= 2;
 
 	usebouncebuf = spi_nor_spimem_bounce(nor, &op);
 
@@ -169,13 +237,11 @@  static ssize_t spi_nor_spimem_write_data(struct spi_nor *nor, loff_t to,
 	ssize_t nbytes;
 	int error;
 
-	op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->write_proto);
-	op.addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->write_proto);
-	op.data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
-
 	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
 		op.addr.nbytes = 0;
 
+	spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
+
 	if (spi_nor_spimem_bounce(nor, &op))
 		memcpy(nor->bouncebuf, buf, op.data.nbytes);
 
@@ -227,10 +293,16 @@  int spi_nor_write_enable(struct spi_nor *nor)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_NO_DATA);
 
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->write_reg(nor, SPINOR_OP_WREN,
-						     NULL, 0);
+		if (spi_nor_protocol_is_dtr(nor->reg_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->write_reg(nor,
+							     SPINOR_OP_WREN,
+							     NULL, 0);
 	}
 
 	if (ret)
@@ -256,10 +328,16 @@  int spi_nor_write_disable(struct spi_nor *nor)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_NO_DATA);
 
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->write_reg(nor, SPINOR_OP_WRDI,
-						     NULL, 0);
+		if (spi_nor_protocol_is_dtr(nor->reg_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->write_reg(nor,
+							     SPINOR_OP_WRDI,
+							     NULL, 0);
 	}
 
 	if (ret)
@@ -318,10 +396,15 @@  static int spi_nor_read_fsr(struct spi_nor *nor, u8 *fsr)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_DATA_IN(1, fsr, 1));
 
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->read_reg(nor, SPINOR_OP_RDFSR,
-						    fsr, 1);
+		if (spi_nor_protocol_is_dtr(nor->reg_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->read_reg(nor, SPINOR_OP_RDFSR,
+							    fsr, 1);
 	}
 
 	if (ret)
@@ -350,9 +433,15 @@  static int spi_nor_read_cr(struct spi_nor *nor, u8 *cr)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_DATA_IN(1, cr, 1));
 
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->read_reg(nor, SPINOR_OP_RDCR, cr, 1);
+		if (spi_nor_protocol_is_dtr(nor->reg_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->read_reg(nor, SPINOR_OP_RDCR,
+							    cr, 1);
 	}
 
 	if (ret)
@@ -383,12 +472,17 @@  int spi_nor_set_4byte_addr_mode(struct spi_nor *nor, bool enable)
 				  SPI_MEM_OP_NO_DUMMY,
 				  SPI_MEM_OP_NO_DATA);
 
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->write_reg(nor,
-						     enable ? SPINOR_OP_EN4B :
-							      SPINOR_OP_EX4B,
-						     NULL, 0);
+		if (spi_nor_protocol_is_dtr(nor->reg_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->write_reg(nor,
+						enable ? SPINOR_OP_EN4B :
+							 SPINOR_OP_EX4B,
+						NULL, 0);
 	}
 
 	if (ret)
@@ -419,10 +513,15 @@  static int spansion_set_4byte_addr_mode(struct spi_nor *nor, bool enable)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_DATA_OUT(1, nor->bouncebuf, 1));
 
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->write_reg(nor, SPINOR_OP_BRWR,
-						     nor->bouncebuf, 1);
+		if (spi_nor_protocol_is_dtr(nor->reg_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->write_reg(nor, SPINOR_OP_BRWR,
+							     nor->bouncebuf, 1);
 	}
 
 	if (ret)
@@ -451,10 +550,16 @@  int spi_nor_write_ear(struct spi_nor *nor, u8 ear)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_DATA_OUT(1, nor->bouncebuf, 1));
 
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->write_reg(nor, SPINOR_OP_WREAR,
-						     nor->bouncebuf, 1);
+		if (spi_nor_protocol_is_dtr(nor->reg_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->write_reg(nor,
+							     SPINOR_OP_WREAR,
+							     nor->bouncebuf, 1);
 	}
 
 	if (ret)
@@ -482,10 +587,16 @@  int spi_nor_xread_sr(struct spi_nor *nor, u8 *sr)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_DATA_IN(1, sr, 1));
 
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->read_reg(nor, SPINOR_OP_XRDSR,
-						    sr, 1);
+		if (spi_nor_protocol_is_dtr(nor->reg_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->read_reg(nor,
+							    SPINOR_OP_XRDSR,
+							    sr, 1);
 	}
 
 	if (ret)
@@ -527,10 +638,16 @@  static void spi_nor_clear_sr(struct spi_nor *nor)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_NO_DATA);
 
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->write_reg(nor, SPINOR_OP_CLSR,
-						     NULL, 0);
+		if (spi_nor_protocol_is_dtr(nor->reg_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->write_reg(nor,
+							     SPINOR_OP_CLSR,
+							     NULL, 0);
 	}
 
 	if (ret)
@@ -591,10 +708,16 @@  static void spi_nor_clear_fsr(struct spi_nor *nor)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_NO_DATA);
 
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->write_reg(nor, SPINOR_OP_CLFSR,
-						     NULL, 0);
+		if (spi_nor_protocol_is_dtr(nor->reg_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->write_reg(nor,
+							     SPINOR_OP_CLFSR,
+							     NULL, 0);
 	}
 
 	if (ret)
@@ -735,10 +858,16 @@  static int spi_nor_write_sr(struct spi_nor *nor, const u8 *sr, size_t len)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_DATA_OUT(len, sr, 1));
 
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->write_reg(nor, SPINOR_OP_WRSR,
-						     sr, len);
+		if (spi_nor_protocol_is_dtr(nor->reg_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->write_reg(nor,
+							     SPINOR_OP_WRSR,
+							     sr, len);
 	}
 
 	if (ret) {
@@ -937,10 +1066,16 @@  static int spi_nor_write_sr2(struct spi_nor *nor, const u8 *sr2)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_DATA_OUT(1, sr2, 1));
 
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->write_reg(nor, SPINOR_OP_WRSR2,
-						     sr2, 1);
+		if (spi_nor_protocol_is_dtr(nor->reg_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->write_reg(nor,
+							     SPINOR_OP_WRSR2,
+							     sr2, 1);
 	}
 
 	if (ret) {
@@ -971,10 +1106,16 @@  static int spi_nor_read_sr2(struct spi_nor *nor, u8 *sr2)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_DATA_IN(1, sr2, 1));
 
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->read_reg(nor, SPINOR_OP_RDSR2,
-						    sr2, 1);
+		if (spi_nor_protocol_is_dtr(nor->reg_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->read_reg(nor,
+							    SPINOR_OP_RDSR2,
+							    sr2, 1);
 	}
 
 	if (ret)
@@ -1002,10 +1143,16 @@  static int spi_nor_erase_chip(struct spi_nor *nor)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_NO_DATA);
 
+		spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
+
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
-		ret = nor->controller_ops->write_reg(nor, SPINOR_OP_CHIP_ERASE,
-						     NULL, 0);
+		if (spi_nor_protocol_is_dtr(nor->write_proto))
+			ret = -ENOTSUPP;
+		else
+			ret = nor->controller_ops->write_reg(nor,
+							     SPINOR_OP_CHIP_ERASE,
+							     NULL, 0);
 	}
 
 	if (ret)
@@ -1144,7 +1291,11 @@  static int spi_nor_erase_sector(struct spi_nor *nor, u32 addr)
 				   SPI_MEM_OP_NO_DUMMY,
 				   SPI_MEM_OP_NO_DATA);
 
+		spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
+
 		return spi_mem_exec_op(nor->spimem, &op);
+	} else if (spi_nor_protocol_is_dtr(nor->write_proto)) {
+		return -ENOTSUPP;
 	} else if (nor->controller_ops->erase) {
 		return nor->controller_ops->erase(nor, addr);
 	}
@@ -2253,6 +2404,7 @@  int spi_nor_hwcaps_read2cmd(u32 hwcaps)
 		{ SNOR_HWCAPS_READ_1_8_8,	SNOR_CMD_READ_1_8_8 },
 		{ SNOR_HWCAPS_READ_8_8_8,	SNOR_CMD_READ_8_8_8 },
 		{ SNOR_HWCAPS_READ_1_8_8_DTR,	SNOR_CMD_READ_1_8_8_DTR },
+		{ SNOR_HWCAPS_READ_8_8_8_DTR,	SNOR_CMD_READ_8_8_8_DTR },
 	};
 
 	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_read2cmd,
@@ -2269,6 +2421,7 @@  static int spi_nor_hwcaps_pp2cmd(u32 hwcaps)
 		{ SNOR_HWCAPS_PP_1_1_8,		SNOR_CMD_PP_1_1_8 },
 		{ SNOR_HWCAPS_PP_1_8_8,		SNOR_CMD_PP_1_8_8 },
 		{ SNOR_HWCAPS_PP_8_8_8,		SNOR_CMD_PP_8_8_8 },
+		{ SNOR_HWCAPS_PP_8_8_8_DTR,	SNOR_CMD_PP_8_8_8_DTR },
 	};
 
 	return spi_nor_hwcaps2cmd(hwcaps, hwcaps_pp2cmd,
@@ -2322,13 +2475,11 @@  static int spi_nor_spimem_check_readop(struct spi_nor *nor,
 					  SPI_MEM_OP_DUMMY(0, 1),
 					  SPI_MEM_OP_DATA_IN(0, NULL, 1));
 
-	op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(read->proto);
-	op.addr.buswidth = spi_nor_get_protocol_addr_nbits(read->proto);
-	op.data.buswidth = spi_nor_get_protocol_data_nbits(read->proto);
-	op.dummy.buswidth = op.addr.buswidth;
 	op.dummy.nbytes = (read->num_mode_clocks + read->num_wait_states) *
 			  op.dummy.buswidth / 8;
 
+	spi_nor_spimem_setup_op(nor, &op, read->proto);
+
 	return spi_nor_spimem_check_op(nor, &op);
 }
 
@@ -2348,9 +2499,7 @@  static int spi_nor_spimem_check_pp(struct spi_nor *nor,
 					  SPI_MEM_OP_NO_DUMMY,
 					  SPI_MEM_OP_DATA_OUT(0, NULL, 1));
 
-	op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(pp->proto);
-	op.addr.buswidth = spi_nor_get_protocol_addr_nbits(pp->proto);
-	op.data.buswidth = spi_nor_get_protocol_data_nbits(pp->proto);
+	spi_nor_spimem_setup_op(nor, &op, pp->proto);
 
 	return spi_nor_spimem_check_op(nor, &op);
 }
@@ -2368,12 +2517,16 @@  spi_nor_spimem_adjust_hwcaps(struct spi_nor *nor, u32 *hwcaps)
 	struct spi_nor_flash_parameter *params = nor->params;
 	unsigned int cap;
 
-	/* DTR modes are not supported yet, mask them all. */
-	*hwcaps &= ~SNOR_HWCAPS_DTR;
-
 	/* X-X-X modes are not supported yet, mask them all. */
 	*hwcaps &= ~SNOR_HWCAPS_X_X_X;
 
+	/*
+	 * If the reset line is broken, we do not want to enter a stateful
+	 * mode.
+	 */
+	if (nor->flags & SNOR_F_BROKEN_RESET)
+		*hwcaps &= ~(SNOR_HWCAPS_X_X_X | SNOR_HWCAPS_X_X_X_DTR);
+
 	for (cap = 0; cap < sizeof(*hwcaps) * BITS_PER_BYTE; cap++) {
 		int rdidx, ppidx;
 
@@ -2628,7 +2781,7 @@  static int spi_nor_default_setup(struct spi_nor *nor,
 		 * controller directly implements the spi_nor interface.
 		 * Yet another reason to switch to spi-mem.
 		 */
-		ignored_mask = SNOR_HWCAPS_X_X_X;
+		ignored_mask = SNOR_HWCAPS_X_X_X | SNOR_HWCAPS_X_X_X_DTR;
 		if (shared_mask & ignored_mask) {
 			dev_dbg(nor->dev,
 				"SPI n-n-n protocols are not supported.\n");
@@ -2774,11 +2927,25 @@  static void spi_nor_info_init_params(struct spi_nor *nor)
 					  SNOR_PROTO_1_1_8);
 	}
 
+	if (info->flags & SPI_NOR_OCTAL_DTR_READ) {
+		params->hwcaps.mask |= SNOR_HWCAPS_READ_8_8_8_DTR;
+		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_8_8_8_DTR],
+					  0, 20, SPINOR_OP_READ_FAST,
+					  SNOR_PROTO_8_8_8_DTR);
+	}
+
 	/* Page Program settings. */
 	params->hwcaps.mask |= SNOR_HWCAPS_PP;
 	spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP],
 				SPINOR_OP_PP, SNOR_PROTO_1_1_1);
 
+	/*
+	 * Since xSPI Page Program opcode is backward compatible with
+	 * Legacy SPI, use Legacy SPI opcode there as well.
+	 */
+	spi_nor_set_pp_settings(&params->page_programs[SNOR_CMD_PP_8_8_8_DTR],
+				SPINOR_OP_PP, SNOR_PROTO_8_8_8_DTR);
+
 	/*
 	 * Sector Erase settings. Sort Erase Types in ascending order, with the
 	 * smallest erase size starting at BIT(0).
@@ -2886,7 +3053,8 @@  static int spi_nor_init_params(struct spi_nor *nor)
 
 	spi_nor_manufacturer_init_params(nor);
 
-	if ((nor->info->flags & (SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ)) &&
+	if ((nor->info->flags & (SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ |
+				 SPI_NOR_OCTAL_READ | SPI_NOR_OCTAL_DTR_READ)) &&
 	    !(nor->info->flags & SPI_NOR_SKIP_SFDP))
 		spi_nor_sfdp_init_params(nor);
 
@@ -2948,7 +3116,9 @@  static int spi_nor_init(struct spi_nor *nor)
 		return err;
 	}
 
-	if (nor->addr_width == 4 && !(nor->flags & SNOR_F_4B_OPCODES)) {
+	if (nor->addr_width == 4 &&
+	    !(nor->info->flags & SPI_NOR_OCTAL_DTR_READ) &&
+	    !(nor->flags & SNOR_F_4B_OPCODES)) {
 		/*
 		 * If the RESET# pin isn't hooked up properly, or the system
 		 * otherwise doesn't perform a reset command in the boot
@@ -3007,6 +3177,9 @@  static int spi_nor_set_addr_width(struct spi_nor *nor)
 {
 	if (nor->addr_width) {
 		/* already configured from SFDP */
+	} else if (spi_nor_protocol_is_dtr(nor->read_proto)) {
+		 /* Always use 4-byte addresses in DTR mode. */
+		nor->addr_width = 4;
 	} else if (nor->info->addr_width) {
 		nor->addr_width = nor->info->addr_width;
 	} else if (nor->mtd.size > 0x1000000) {
@@ -3244,14 +3417,19 @@  static int spi_nor_create_read_dirmap(struct spi_nor *nor)
 	};
 	struct spi_mem_op *op = &info.op_tmpl;
 
-	/* get transfer protocols. */
-	op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->read_proto);
-	op->addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->read_proto);
-	op->dummy.buswidth = op->addr.buswidth;
-	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto);
+	spi_nor_spimem_setup_op(nor, op, nor->read_proto);
 
 	/* convert the dummy cycles to the number of bytes */
 	op->dummy.nbytes = (nor->read_dummy * op->dummy.buswidth) / 8;
+	if (spi_nor_protocol_is_dtr(nor->read_proto))
+		op->dummy.nbytes *= 2;
+
+	/*
+	 * Since spi_nor_spimem_setup_op() only sets buswidth when the number
+	 * of data bytes is non-zero, the data buswidth won't be set here. So,
+	 * do it explicitly.
+	 */
+	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto);
 
 	nor->dirmap.rdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
 						       &info);
@@ -3270,15 +3448,18 @@  static int spi_nor_create_write_dirmap(struct spi_nor *nor)
 	};
 	struct spi_mem_op *op = &info.op_tmpl;
 
-	/* get transfer protocols. */
-	op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->write_proto);
-	op->addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->write_proto);
-	op->dummy.buswidth = op->addr.buswidth;
-	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
-
 	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
 		op->addr.nbytes = 0;
 
+	spi_nor_spimem_setup_op(nor, op, nor->write_proto);
+
+	/*
+	 * Since spi_nor_spimem_setup_op() only sets buswidth when the number
+	 * of data bytes is non-zero, the data buswidth won't be set here. So,
+	 * do it explicitly.
+	 */
+	op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
+
 	nor->dirmap.wdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
 						       &info);
 	return PTR_ERR_OR_ZERO(nor->dirmap.wdesc);
diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
index 6f2f6b27173f..de1e3917889f 100644
--- a/drivers/mtd/spi-nor/core.h
+++ b/drivers/mtd/spi-nor/core.h
@@ -62,6 +62,7 @@  enum spi_nor_read_command_index {
 	SNOR_CMD_READ_1_8_8,
 	SNOR_CMD_READ_8_8_8,
 	SNOR_CMD_READ_1_8_8_DTR,
+	SNOR_CMD_READ_8_8_8_DTR,
 
 	SNOR_CMD_READ_MAX
 };
@@ -78,6 +79,7 @@  enum spi_nor_pp_command_index {
 	SNOR_CMD_PP_1_1_8,
 	SNOR_CMD_PP_1_8_8,
 	SNOR_CMD_PP_8_8_8,
+	SNOR_CMD_PP_8_8_8_DTR,
 
 	SNOR_CMD_PP_MAX
 };
@@ -311,6 +313,7 @@  struct flash_info {
 					 * BP3 is bit 6 of status register.
 					 * Must be used with SPI_NOR_4BIT_BP.
 					 */
+#define SPI_NOR_OCTAL_DTR_READ	BIT(19) /* Flash supports octal DTR Read. */
 
 	/* Part specific fixup hooks. */
 	const struct spi_nor_fixups *fixups;
@@ -399,6 +402,9 @@  extern const struct spi_nor_manufacturer spi_nor_winbond;
 extern const struct spi_nor_manufacturer spi_nor_xilinx;
 extern const struct spi_nor_manufacturer spi_nor_xmc;
 
+void spi_nor_spimem_setup_op(const struct spi_nor *nor,
+			     struct spi_mem_op *op,
+			     const enum spi_nor_protocol proto);
 int spi_nor_write_enable(struct spi_nor *nor);
 int spi_nor_write_disable(struct spi_nor *nor);
 int spi_nor_set_4byte_addr_mode(struct spi_nor *nor, bool enable);
diff --git a/drivers/mtd/spi-nor/sfdp.c b/drivers/mtd/spi-nor/sfdp.c
index f6038d3a3684..f917631c8110 100644
--- a/drivers/mtd/spi-nor/sfdp.c
+++ b/drivers/mtd/spi-nor/sfdp.c
@@ -1044,9 +1044,16 @@  static int spi_nor_parse_4bait(struct spi_nor *nor,
 	}
 
 	/* 4BAIT is the only SFDP table that indicates page program support. */
-	if (pp_hwcaps & SNOR_HWCAPS_PP)
+	if (pp_hwcaps & SNOR_HWCAPS_PP) {
 		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP],
 					SPINOR_OP_PP_4B, SNOR_PROTO_1_1_1);
+		/*
+		 * Since xSPI Page Program opcode is backward compatible with
+		 * Legacy SPI, use Legacy SPI opcode there as well.
+		 */
+		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP_8_8_8_DTR],
+					SPINOR_OP_PP_4B, SNOR_PROTO_8_8_8_DTR);
+	}
 	if (pp_hwcaps & SNOR_HWCAPS_PP_1_1_4)
 		spi_nor_set_pp_settings(&params_pp[SNOR_CMD_PP_1_1_4],
 					SPINOR_OP_PP_1_1_4_4B,
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index bebff2729c18..d251a5d02be2 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -182,6 +182,7 @@  enum spi_nor_protocol {
 	SNOR_PROTO_1_2_2_DTR = SNOR_PROTO_DTR(1, 2, 2),
 	SNOR_PROTO_1_4_4_DTR = SNOR_PROTO_DTR(1, 4, 4),
 	SNOR_PROTO_1_8_8_DTR = SNOR_PROTO_DTR(1, 8, 8),
+	SNOR_PROTO_8_8_8_DTR = SNOR_PROTO_DTR(8, 8, 8),
 };
 
 static inline bool spi_nor_protocol_is_dtr(enum spi_nor_protocol proto)
@@ -228,7 +229,7 @@  struct spi_nor_hwcaps {
  * then Quad SPI protocols before Dual SPI protocols, Fast Read and lastly
  * (Slow) Read.
  */
-#define SNOR_HWCAPS_READ_MASK		GENMASK(14, 0)
+#define SNOR_HWCAPS_READ_MASK		GENMASK(15, 0)
 #define SNOR_HWCAPS_READ		BIT(0)
 #define SNOR_HWCAPS_READ_FAST		BIT(1)
 #define SNOR_HWCAPS_READ_1_1_1_DTR	BIT(2)
@@ -245,11 +246,12 @@  struct spi_nor_hwcaps {
 #define SNOR_HWCAPS_READ_4_4_4		BIT(9)
 #define SNOR_HWCAPS_READ_1_4_4_DTR	BIT(10)
 
-#define SNOR_HWCAPS_READ_OCTAL		GENMASK(14, 11)
+#define SNOR_HWCAPS_READ_OCTAL		GENMASK(15, 11)
 #define SNOR_HWCAPS_READ_1_1_8		BIT(11)
 #define SNOR_HWCAPS_READ_1_8_8		BIT(12)
 #define SNOR_HWCAPS_READ_8_8_8		BIT(13)
 #define SNOR_HWCAPS_READ_1_8_8_DTR	BIT(14)
+#define SNOR_HWCAPS_READ_8_8_8_DTR	BIT(15)
 
 /*
  * Page Program capabilities.
@@ -260,18 +262,19 @@  struct spi_nor_hwcaps {
  * JEDEC/SFDP standard to define them. Also at this moment no SPI flash memory
  * implements such commands.
  */
-#define SNOR_HWCAPS_PP_MASK	GENMASK(22, 16)
-#define SNOR_HWCAPS_PP		BIT(16)
+#define SNOR_HWCAPS_PP_MASK		GENMASK(23, 16)
+#define SNOR_HWCAPS_PP			BIT(16)
 
-#define SNOR_HWCAPS_PP_QUAD	GENMASK(19, 17)
-#define SNOR_HWCAPS_PP_1_1_4	BIT(17)
-#define SNOR_HWCAPS_PP_1_4_4	BIT(18)
-#define SNOR_HWCAPS_PP_4_4_4	BIT(19)
+#define SNOR_HWCAPS_PP_QUAD		GENMASK(19, 17)
+#define SNOR_HWCAPS_PP_1_1_4		BIT(17)
+#define SNOR_HWCAPS_PP_1_4_4		BIT(18)
+#define SNOR_HWCAPS_PP_4_4_4		BIT(19)
 
-#define SNOR_HWCAPS_PP_OCTAL	GENMASK(22, 20)
-#define SNOR_HWCAPS_PP_1_1_8	BIT(20)
-#define SNOR_HWCAPS_PP_1_8_8	BIT(21)
-#define SNOR_HWCAPS_PP_8_8_8	BIT(22)
+#define SNOR_HWCAPS_PP_OCTAL		GENMASK(23, 20)
+#define SNOR_HWCAPS_PP_1_1_8		BIT(20)
+#define SNOR_HWCAPS_PP_1_8_8		BIT(21)
+#define SNOR_HWCAPS_PP_8_8_8		BIT(22)
+#define SNOR_HWCAPS_PP_8_8_8_DTR	BIT(23)
 
 #define SNOR_HWCAPS_X_X_X	(SNOR_HWCAPS_READ_2_2_2 |	\
 				 SNOR_HWCAPS_READ_4_4_4 |	\
@@ -279,10 +282,14 @@  struct spi_nor_hwcaps {
 				 SNOR_HWCAPS_PP_4_4_4 |		\
 				 SNOR_HWCAPS_PP_8_8_8)
 
+#define SNOR_HWCAPS_X_X_X_DTR	(SNOR_HWCAPS_READ_8_8_8_DTR |	\
+				 SNOR_HWCAPS_PP_8_8_8_DTR)
+
 #define SNOR_HWCAPS_DTR		(SNOR_HWCAPS_READ_1_1_1_DTR |	\
 				 SNOR_HWCAPS_READ_1_2_2_DTR |	\
 				 SNOR_HWCAPS_READ_1_4_4_DTR |	\
-				 SNOR_HWCAPS_READ_1_8_8_DTR)
+				 SNOR_HWCAPS_READ_1_8_8_DTR |	\
+				 SNOR_HWCAPS_READ_8_8_8_DTR)
 
 #define SNOR_HWCAPS_ALL		(SNOR_HWCAPS_READ_MASK |	\
 				 SNOR_HWCAPS_PP_MASK)
@@ -318,6 +325,22 @@  struct spi_nor_controller_ops {
 	int (*erase)(struct spi_nor *nor, loff_t offs);
 };
 
+/**
+ * enum spi_nor_cmd_ext - describes the command opcode extension in DTR mode
+ * @SPI_NOR_EXT_NONE: no extension. This is the default, and is used in Legacy
+ *		      SPI mode
+ * @SPI_NOR_EXT_REPEAT: the extension is same as the opcode
+ * @SPI_NOR_EXT_INVERT: the extension is the bitwise inverse of the opcode
+ * @SPI_NOR_EXT_HEX: the extension is any hex value. The command and opcode
+ *		     combine to form a 16-bit opcode.
+ */
+enum spi_nor_cmd_ext {
+	SPI_NOR_EXT_NONE = 0,
+	SPI_NOR_EXT_REPEAT,
+	SPI_NOR_EXT_INVERT,
+	SPI_NOR_EXT_HEX,
+};
+
 /*
  * Forward declarations that are used internally by the core and manufacturer
  * drivers.
@@ -345,6 +368,7 @@  struct spi_nor_flash_parameter;
  * @program_opcode:	the program opcode
  * @sst_write_second:	used by the SST write operation
  * @flags:		flag options for the current SPI-NOR (SNOR_F_*)
+ * @cmd_ext_type:	the command opcode extension type for DTR mode.
  * @read_proto:		the SPI protocol for read operations
  * @write_proto:	the SPI protocol for write operations
  * @reg_proto:		the SPI protocol for read_reg/write_reg/erase operations
@@ -376,6 +400,7 @@  struct spi_nor {
 	enum spi_nor_protocol	reg_proto;
 	bool			sst_write_second;
 	u32			flags;
+	enum spi_nor_cmd_ext	cmd_ext_type;
 
 	const struct spi_nor_controller_ops *controller_ops;